Practice ammunition



NOV. 4, 1969 GAWUQK ET AL 3,476,049

PRACTICE AMMUNITION Filed May 17, 1967 INVENTORS H EINZ GAWLICK RUDOLF STAHLMANN BY w ATTORNEYS United States Patent Ufifice 3,476,949 Patented Nov. 4, 1969 0, 24 Int. Cl. F42b 11/18, 13/20 US. Cl. 10292.7 Claims ABSTRACT OF THE DISCLOSURE The present disclosure relates to a practice or training projectile that has a reduced cross section so that only a portion of the propellant powder charge energy is utilized as corresponds to the reduced cross section of the projectile and thus a short distance of travel is obtained. The cross section is reduced by providing a tubular projectile body having an axially extending bore throughout its entire length. The opposite ends of the tubular body may be tapered and provided respectively with a front tip insert and a rear plug to more closely simulate a live projectile; the insert and the plug separating from the tubular body during firing.

The invention of the present application is an improvement over a training ammunition wherein the projectile, constructed as in the case of corresponding live ammunition, is provided with a central axial bore extending throughout its entire length. By this measure, the cross section of the projectile is reduced so that only a portion of the propellant powder energy is utilized as corresponds to the reduced cross section of the projectile and thus a short distance of travel is obtained. The flight distance of the projectile may be varied at will within relatively wide limits by correspondingly dimensioning the inside cross section of the bore extending through the projectile. It is possible to exceed the ratio of the inside cross section of the projectile bore to the caliber of the projectile of about 1:3 disclosed in the above mentioned application; this ratio may in fact extend up to about 1:2, whereby the flight distance of the shell is even further decreased. The flight range may be decreased further by roughening the inside surface of the bore, instead of making it smooth.

It is a feature of the present invention to further reduce the flight distance of the projectile by constructing it as a hollow cylindrical body having an outer end surface, which is at right angles to the axis of the shell, at least at the front end.

If a practice projectile simulating live ammunition having an ogival tip was provided with an axially extending bore throughout its entire length, there would result a sharp edge at the front end. According to the present invention, if such a shell is desired the front end may more or less be blunted by shortening the length of the shell at the front end to a quarter or less extent so that a correspondingly broad, annular front face is formed. When an insert is provided in the front end of such a projectile, it must be made correspondingly longer to the extent that the main body portion was shortened as above mentioned to regain the original simulated shape, according to the present invention.

Instead of exactly simulating live ammunition, it is contemplated that the hollow cylindrical tubular body may be provided at its front and/or rear end on the outside with a conical taper, that is to give the projectile body, as the simplest form, the shape of a rotational body. Here again, the body may be supplemented by a special insert to regain the full shape of live ammunition.

Further features, variations, embodiments and advantages of the present invention will become more clear in connection with the following detailed description of the drawings, wherein:

FIGURE 1 is a longitudinal cross sectional view of a training projectile body having conically tapered ends;

FIGURE 2 shows the projectile body of FIGURE 1, in cross section, supplemented to the full shape of live ammunition by suitable inserts; and

FIGURE 3 shows a modification of the FIGURE 2 construction.

As shown in FIGURE 1, the tubular cylindrical projectile body 1 is provided with a central axially extending bore 2 that extends throughout the longitudinal length of the tubular body 1. The outer surface of the front end 3 of the projectile is conically tapered forwardly toward the projectile axis and the outer surface of the rear end is conically tapered rearwardly toward the projectile axis. The rear tapering may be steeper than the front tapering, as shown, or the two tapers may have identical angles with respect to the axis; also, it is contemplated that the front taper may be the steepest. The projectile of FIGURE 1 may be used alone or in combination with the features of FIGURE 2.

As shown in FIGURE 2, the front end of the tubular body 1 is provided with a solid tip insert 5 that has a rearwardly extending projection 6 frictionally and telescopically engaging in the bore 2; this insert supplements the tubular body 1 with respect to its external configuration so that it conforms to the complete external shape of a conventional projectile. The rearward end of the bore 2 may frictionally and telescopically contain the rearwardly extending projection or lug 7 of a rear plug having a rearward flange 8 radially overlapping the rear end of the tubular body 1. Upon firing, the flange 8 is easily sheared off by the pressure of the propellant gases and the lug 7 then constitutes a piston having a maximum external diameter equal to the internal diameter of the tubular body bore 2 so that it will travel forwardly through the bore 2 to strike the rearward end of the tip insert 5 for driving the tip insert and piston completely out of engagement with the tubular body, which travels by itself to the target.

In the embodiment of FIGURE 3, the projectile is constructed substatnially identical to the embodiment of FIG- URE 2, except that the rear plug 9 is provided with a forwardly extending projection 10 inserted into the rear end of the bore 2, instead of the lug 7 of FIGURE 2. At the transition from the hollow cylindrical portion of the rear plug, there is provided a weakened zone that will be sheared under the effect of the propellant powder gases during firing. The external diameter of the rearward cylindrical tubular extension is substantially the same as the rearmost outer diameter of the tubular body rear end and the internal diameter of the cylindrical rear plug extension is substantially equal to the internal diameter of the bore 2. During firing, the projection 10 is sheared from the other parts of the rear plug 9 to constitute a piston for traveling forwardly through the bore 2, striking the rearward projection 6 and pushing the tip insert 5 by means of the projection 6 out of the front of the bore 2, so that again the tubular body 1 will travel by itself to the target as in the manner discussed in regard to FIGURE 2. Because of the relatively large radially extending front surface 11 of the tubular body 1 and the bore 2, the tubular body is braked and accordingly flies only a very short distance.

We claim:

1. A practice projectile, comprising: a substantially tubular projectile body having an axially extending bore throughout its entire axial extent; said tubular body having a front end and a rear end; said front end having a front end face extending at substantially right angles to the projectile axis to constitute means providing air resistance by direct air contact over the entire end face during free flight after firing to reduce the velocity and range of the practice projectile; at least one of said ends having an outer surface conically tapering towards said axis and away from the geometric center of the projectile; a solid tip insert having an outer surface configuration forwardly tapered toward said axis and substantially flush with said front end outer surface; said insert having a rearwardly extending projection frictionally and telescopically engaged in the bore of said tubular body to form connection means readily releasable during firing to separate said tip and said tubular body; including a rear plug having a forwardly extending projection frictionally and telescopically engaged in the rear end of the bore of said tubular body and having a rearward flange radially overlapping the rear end of said tubular body; said rearward flange includ ing means for producing a shear to separate said rearward flange and forward projection upon firing of said projectile to constitute said forward projection, a piston'having a maximum external diameter substantially equal to the internal diameter of said tubular body bore for traveling forwardly in said bore to strike the rearward end of said tip insert rearward projection for driving said tip insert and piston means completely out of engagement with said tubular body so said tubular body will travel alone to the intended target.

2. The projectile according to claim 1, wherein said rear plug includes :a substantially cylindrical tubular por tion having an internal diameter substantially equal to the internal diameter of said tubular body bore, being integrally connected at its forward end to said rearward flange and extending rearwardly therefrom an axial distance at least equal to its diameter; the other diameter of said cylindrical tubular portion being substantially equal to the rear most outer diameter of said tubular body rear end. 1

3. The projectile according to claim 1, wherein said at least one of said ends is the forward end; and said rear end has an outer surface conically tapering rearwardly toward said axis.

4. The projectile according to claim 3 wherein said rear plug includes a substantially cylindrical tubular portion having an internal diameter substantially equal to the internal diameter of said tubular body bore, being integrally connected at its forward end to said rearward flange and extending rearwardly therefrom an axial distance at least equal to its diameter; the other diameter of said cylindrical tubular portion being substantially equal to the rear most outer diameter of said tubular body rear end.

5. The projectile according to claim 4 wherein said tubular body bore has a roughened surface.

References Cited UNITED STATES PATENTS 1927 Great Britain.

ROBERT F. STAHL, Primary Examiner 

